function _init()
game_over = false
make_cave()
make_player()
end

function _update()
if (not game_over) then
update_cave()
move_player()
check_hit()
else
if (btnp(5)) _init() -- restart
end
end

function _draw()
cls() -- clear screen
draw_cave()
draw_player()

if (game_over) then
    print("game over!", 44, 44, 7)
    print("your score: " .. player.score, 34, 54, 7)
    print("press ❎ to play again!", 18, 72, 6)
else
    print("score: " .. player.score, 2, 2, 7)
    -- Display health
    print("health: " .. player.health, 2, 12, 7)
end

end

function make_player()
player = {}
player.x = 24 -- position
player.y = 60
player.dy = 0 -- fall speed
player.rise = 1 -- sprites
player.fall = 2
player.dead = 3
player.speed = 2 -- fly speed
player.score = 0
player.health = 3 -- starting health
end

function draw_player()
if (game_over) then
spr(player.dead, player.x, player.y)
elseif (player.dy < 0) then
spr(player.rise, player.x, player.y)
else
spr(player.fall, player.x, player.y)
end
end

function move_player()
gravity = 0.2 -- bigger means more gravity
player.dy += gravity -- add gravity

-- jump
if (btnp(2)) then
    player.dy -= 5
    sfx(0)
end

-- move to new position
player.y += player.dy

-- update score
player.score += player.speed

end

function check_hit()
for i = player.x, player.x + 7 do
if (cave[i + 1].top > player.y or cave[i + 1].btm < player.y + 7) then
-- Decrease health when hitting a wall instead of ending the game
player.health -= 1
sfx(1)

        if player.health <= 0 then
            game_over = true
        end
    end
end

end

function make_cave()
cave = {["top"] = 5, ["btm"] = 119}
top = 45 -- how low can the ceiling go
btm = 85 -- how high can the floor get
end

function update_cave()
-- remove the back of the cave
if (#cave > player.speed) then
for i = 1, player.speed do
del(cave, cave[1])
end
end

-- add more cave
while (#cave < 128) do
    local col = {}
    local up = flr(rnd(7) - 3)
    local dwn = flr(rnd(7) - 3)
    col.top = mid(3, cave[#cave].top + up, top)
    col.btm = mid(btm, cave[#cave].btm + dwn, 124)
    add(cave, col)
end

end

function draw_cave()
top_color = 2 -- play with these
btm_color = 1 -- choose own colors
for i = 1, #cave do
line(i - 1, 0, i - 1, cave[i].top, top_color)
line(i - 1, 127, i - 1, cave[i].btm, btm_color)
end
end